Apparently healthy elderly donors were screened according to a simple
protocol that included clinical examination and the determination of h
ematological and biochemical values. This screening was performed to d
etect subclinical alterations which might interfere with immune respon
ses and trace element status. The elderly were divided into two groups
. The first group consisted of 22 (age 76 +/- 1 years) positively sele
cted elderly (PSE), i.e. healthy subjects with no hematological and la
boratory alterations, the second one comprised 13 (age 75 +/- 1 years)
negatively selected elderly CNSE). Data were then compared with those
obtained from 40 (age 35 +/- 2 years) healthy young controls. In both
groups of elderly donors, plasma zinc levels were normal, while plasm
a copper concentrations were increased. Intracellular values of zinc a
nd copper in mono- and polymorphonuclear cells from both groups of eld
erly were within reference limits. After in vitro activation, granuloc
yte chemiluminescence activity was impaired only in NSE. A decrement i
n the number of circulating CD3 lymphocytes and an increase in CD8d, C
D57 cells were found in PSE, while NSE showed an increased number of C
D3,DR cells and CD8d,CD57, CD8b,CD57 and CD16,CD56 positive cells. Our
results indicate that only plasma copper levels were affected by age,
whereas subclinical alterations in hematological or biochemical value
s appear to impair immune responses in the elderly.